Center air conditioning cold then room temperature

I live in south Louisiana. Summer temperatures, like always, have been high and naturally, we're having air conditioning trouble. Inside unit began squeaking one night last week around 11 PM. It was determined to be a bearing and the repairman said would be easier just to replace the old motor. The repairman replaced the blower motor and I also had him recharge freon in the unit. He said it was low 5-7 pounds and there is a slow leak. This had been told to me before by a different tech/different company last year, so not a surprise. Had unit serviced and refrigerant recharged last April.

This is a 3-ton Trane outside unit from 1995 and the inside unit is apparently from 87 or so. I can't afford (unless I guess that's the only option) to replace everything right now, so please don't suggest that. Obviously, that's the ultimate answer. Old stuff breaks.

Moving on..

CURRENT PROBLEM:

Unit was cooling the house wonderfully since the new blower motor was installed. Then, today, we realized the house was a little warm. Put hand near vents and the air was room temperature. Blower motor seems to be still working so went outside and compressor seems not to have kicked on? It was a little quiet, but the compressor fan was spinning.

Turned the unit off for about 5 minutes. Then, it cooled again for an hour or so. Then, same scenario. Now, it's been off an hour and I just tried again and nothing.

Now, of course I am thinking the repairman either overcharged the unit (is that possible?) or hooked something up wrong, but probably unlikely since it was working excellent for a few days. I guess it should be for $600...

What could this be? Could it be the battery-operated Pro1 thermostat that the last tech installed a year ago to replace the analog one? Could it just be the compressor dying? Something else? My research makes me think it's an electrical problem?

Please help. I'm sitting here sweating. I have called the repairman and they are sending the guy back out on Monday, but I can't live in this house in Louisiana summer. It's blazing outside. Need help quick.

Center air conditioning cold then room temperature

If the freon has leaked out of the system, time to start pricing out a new unit. Most likely the A-coil is so bad, that it is a part of the problem, not just a slow leak. First off, update with location, and either have the prev. tech come out and do a complete testing of the system to determine if it is worthwhile wasting more freon, or if best to replace the complete system both inside & out, including A-Coil.

Center air conditioning cold then room temperature

If you were overcharged, I would think that the compressor would cut out quicker than yours is... or not cut out at all. It DOES sound like the compressor is overheating.
If your system was 5 - 7 pounds low, it was nearly empty! Leak might be worse than you think. Or you were charged for refrigerant you didn't get.
I'd suggest checking the compressor capacitor. See this video: http://youtu.be/2N_t6d0fSbw

Center air conditioning cold then room temperature

Quote:

Originally Posted by TopTechnician

If you were overcharged, I would think that the compressor would cut out quicker than yours is... or not cut out at all. It DOES sound like the compressor is overheating.
If your system was 5 - 7 pounds low, it was nearly empty! Leak might be worse than you think. Or you were overcharged.
I'd suggest checking the compressor capacitor. See this video: http://youtu.be/2N_t6d0fSbw

Would the tech not have checked the capacitor? Just wondering. He seemed reputable and smart.

Center air conditioning cold then room temperature

Yes, I'm sure... but capacitors go bad all the time, and though it would be quite a coincidence, I'd still recommend checking it.
Do you have a thermometer with which you can compare supply and return air temperatures? If you are losing refrigerant fast enough that you are low again already, then the compressor could be overheating.
15 to 20 degrees would be an acceptable temperature drop from return to supply. Less than that would indicate low refrigerant.

Center air conditioning cold then room temperature

Can't replace entire unit. Don't have the funds. Working now, but doesn't seem to be cooling as well.

I am not an expert. I am a homeowner and have 6 central units at my building.

The other fellas and maybe gals) here are better advice. I am just trying to help because you are short on funds. If the condensor unit outside is bad, you might want to search out craiglist for a used outside condensor unit. Poke around Appliances and serach for air conditioner

Center air conditioning cold then room temperature

natedro, I got lucky, and my guy that does our hvac & plumbing, that is a brother of one of the lady's that my wife works with, allowed us to make payments on the install for our a/c & a-coil install. Otherwise, I would not have had the $2100 up front to do ours.

I would not touch a used equipment sell with a ten foot pole. That is just my opinion. I have a Armstrong Air outside unit, which is made by Lennox but is actually 1/2 the cost of their equipment, just because it does not have the Lennox plate on it, but the insides are all Lennox. Alpinehomeair.com sells Goodman equipment They have Scratch & Dent & Overstock equipment on sale right now, with some starting at $430. You just have to supply the help to get it off the truck when it is delivered, and the tech to install, but you could probably save a lot of money on the complete setup, vs. going with some local doing a huge markup on equipment.

Find a lone small business owner like we did to do your work, and check out the current unit, that has been in the business for a long time not just some guy or gal that just got out of school, or just started working for the company in the past two years.

Center air conditioning cold then room temperature

The problem is, your smaller lineset is freezing which means something is not correct. Get the tech or another tech out there, and leave it off so that no further damage happens, until they check it out. Show them the picture of the small line freezing.

Center air conditioning cold then room temperature

Quote:

The problem is, your smaller lineset is freezing which means something is not correct

That looks like paint or something else on the small line (the liquid line), not ice or frost. If the liquid line is freezing immediately out of the unit, you've got a significant restriction in the condenser section somewhere.